For years there have been a multitude of attempts and ideas for providing a satisfactory seal when a shaft is angularly misaligned from the bore and the shaft runs out.
The problem is especially acute in air barrier seals where the shaft to bore misalignment is maximized. The solution requires both the tight running clearance between the seal members and the stationary member and a loose running clearance for adjustment for operational conditions especially misalignment of the shaft with respect to the stator or stationary member.
Prior uses of air pressure to seal both liquid and solid materials have not been entirely satisfactory because of the inherent tight clearance necessary to create the required air pressure in the seal greater than the pressure of the product on the other side of the seal.
This is to say that to ensure proper sealing, i.e. the tighter the seal less volume of air is required to maintain the seal against the external pressure of material.
Shaft misalignment is also a problem with contact seals with the contact resulting in greater wear due to the misalignment. Abrasiveness of the product also affects the wear pattern and the useful life of the seals.
Thus the seal operates with a low or tight running clearance that can be maintained when the operational demands result in misalignment of the rotating shaft with respect to the fixed element occurs. This invention provides a tight seal for air and or fluids barrier seals over a relatively large range of misalignment of the shaft to the bore. This tight seal can also be used with contact seals to augment the performance by redistributing the friction equally as the surface face is maintained at a predetermined tight clearance even as misalignment occurs.